RESUMO
Mycobacterium massiliense is an environmental opportunistic pathogen that has been associated with soft tissue infection after minor surgery. We studied the acute immune response of C57BL/6 and BALB/c mice infected intravenously with 10(6) CFU of an M. massiliense strain isolated from a nosocomial infection in Brazil. The results presented here show that M. massiliense is virulent and pathogenic to both C57BL/6 and BALB/c mice, inducing a granulomatous inflammatory reaction that involves the activation of macrophages, dendritic cells, and natural killer cells induced by gamma interferon and interleukin-17 (IL-17) in C57BL/6 mice and by IL-12 in BALB/c mice.
Assuntos
Infecções por Mycobacterium/imunologia , Infecções por Mycobacterium/patologia , Mycobacterium/imunologia , Mycobacterium/patogenicidade , Animais , Bacteriemia/imunologia , Bacteriemia/patologia , Brasil , Infecção Hospitalar/microbiologia , Células Dendríticas/imunologia , Modelos Animais de Doenças , Feminino , Granuloma/imunologia , Granuloma/microbiologia , Granuloma/patologia , Humanos , Interferon gama/imunologia , Interleucina-17/imunologia , Células Matadoras Naturais/imunologia , Fígado/microbiologia , Fígado/patologia , Pulmão/microbiologia , Pulmão/patologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium/microbiologia , Baço/microbiologia , Baço/patologia , VirulênciaRESUMO
A cluster of surgical site infection cases after arthroscopic and laparoscopic procedures occurred between 2005 and 2007 in Goiânia, in the central region of Brazil. Nontuberculous mycobacteria (NTM) were isolated from samples (exudates from cutaneous abscesses) from 18 patients of seven private hospitals. There were no reports of post-surgical arthroscopic and laparoscopic mycobacterial infections in Goiânia apart from this period. The 18 isolates were identified as Mycobacterium massiliense by PCR-restriction digestion of the hsp65 gene, pulsed-field gel electrophoresis (PFGE) comparisons, and rpoB partial gene sequencing. All isolates were typed as a single clone, indicating that they have the same origin, which suggests a common source of infection for all patients.